Exhibit 99.1 C3is Inc. C3is Inc. reports second quarter and six months 2023 financial and operating results Athens, Greece, September 1, 2023 – C3is Inc. (Nasdaq: CISS) (the "Company"), a ship-owning company providing drybulk and tanker seaborne transportation services, and from Q3 2023, tanker transportation services, announced today its unaudited financial and operating results for the second quarter and six months ended June 30, 2023. These financial results were based on the accounts of C3is Inc. and it ...